What and where is good to go and see and experience in the USA?

All nice suggestions but it can only can be Trumped by seeing the national comedian......., the Donald....

Don't forget the flyover states. I spent a large part of last year working In Knoxville, Tennessee.  Eating fried catfish at a little restaurant on a creek, shooting handguns at an open air range in the woods and watching collage football (go Vols!) may not be the best America has to offer.  But it sure gave a taste of what real Americamis like away from the coasts. 

While I see that Florida has been mentioned, and the gulf coast is lovely, I'm a little surprised that no-one has mentioned the amusement parks.  If you do only one, do Magic Kingdom. In my first family holiday to Florida I was persuaded by the wife and kids that it would be fun.  I didn't fancy it at all and rather grumpily (no pun intended) went along with my expectations being that I'd at least enjoy seeing the family enjoy itself.  Gosh, was I wrong.  The scale, the attention to detail, the effort put into the whole customer experience just blew me away.  The USA is just so professional at this sort of thing, even a grumpy, somewhat cynical Englishman like me couldn't help but get swept up in the magic of the thing. Universal is pretty similar but without so many parades and more adult humour. Experiencing the parks should be on everyone's bucket list.

Yep, Disney World Resort in Orlando is really a magical world. 

Hate to agree with MDS , but I visited disney 20 years ago, it was Ok but kids were too young for many rides, not a great trip. Now my American born youngest is 18 we have visited twice, I did not think I would enjoy. We have stayed at Disney Animal kingdom lodge and this year the Polynesian, just wonderful. Each to their own, I actually enjoyed an air boat ride in the Everglades, as much as the parks. Try the Yachtsmen steak house at the same Disney hotel, pricey, but wow!

I should also have added, if you're in Florida, the Kennedy Space Centre is treat.  The tour about the moon landings is hugely impressive. I can still recall emerging under the Saturn 5 rocket and the 'wow' moment. How the hell can anything that huge get off the ground?!! And the thought that the module and lander had computing power no much better than a Sinclair ZX Spectrum beggars belief.  

I  liked the Grand Canyon but thought that Bryce Canyon was even more magical.

Or let Disney do it for you at Epcot with mission space, the green ticket now takes you around earth in space, the orange ticket is through space to mars. We did the mars trip, it's a flight simulator which cost Disney $100 mil. Well the blast off and g force was a new experience, then weightless flight and the landing on mars. Realistic is not the right word, as how would I know........but boy did I feel "seasick" at the end.

Enjoy....

Agreed, Bryce Canyon is truly spectacular,  the rock formations are something really special.  Grand Canyon is mind blowing in its size, I found it almost too big to take it all in.   Horseshoe Bend on Hwy 89 at the very top end of the Colorado gorge (Grand Canyon)  just outside Page is another must see while in the area.     

If you go to Monument Valley,  another don't miss in the area is Canyon de Chelly;  steep (shear) sided red sandstone about 300m deep & only a few hundred metres wide in places.  Its easy to access & view on north & south rim drives.  People have lived there for 5000 years & still do.  

Gazza posted:

Or let Disney do it for you at Epcot with mission space, the green ticket now takes you around earth in space, the orange ticket is through space to mars. We did the mars trip, it's a flight simulator which cost Disney $100 mil. Well the blast off and g force was a new experience, then weightless flight and the landing on mars. Realistic is not the right word, as how would I know........but boy did I feel "seasick" at the end.

Enjoy....

I agree Gazza. Mission Space is by far and away the most stunning game-park ride I've ever experienced. Two of my kids who accompanied on it were teenagers at the time and over a decade later and many other  different rides in between Mission Space is still 'the one' for them.  

For Urban experience:

1 Chicago

2. Seattle

3. San Francisco 

4. Las Vegas

5. New York

Depends in what you like to do/see. For outdoors:

1. Alaska Anchorage-> Denali-> Fairbanks -> arctic circle -> Pruhoe Bay

2. Wyoming Yellowstone National Park

3. Nevada/California -> Yosemite National Park, Grand Canyon, Death Valley National Park, Area 51

For broad overview:

Fly into Chicago and drive the famous Route 66 -> California.

Highway 1 along the Pacific coast - All the way from San Diego to the north to beach towns, to the bustle and excitement of Los Angeles, through elegant Santa Barbara and surrounding wine country, then to the north again to more, and more beaches and attractions in Carmel, Monterey, and Santa Cruz, end up in the ultimate “City by the Bay,” San Francisco.

This route is exactly the reason why I love and appreciate  the USA.

why not continue north over the Golden Gate Bridge through Northern California, into Oregon and Washington States to the Canadian border (and into Vancouver)

however you will probably have to exchange your rental car at the border ie Seattle and Vancouver.

It can rain a lot but you will get to see lots of trees mountains etc.

However not as fascinating as a big circle starting at Phoenix going via Las Vegas, Page, Boulder, Santa Fe,  Las Cruces, Tucson and back to PHX picking up as many national parks as you can fit into the trip. Plus quite a few good art galleries as well. 

Santa Barbara is a wonderful city, incredible views, take whale watching tours or out to the Channel Islands each one has it's own endemic plants.  The mountains are beautiful but I worked for the Forest Service and with budget cuts the campgrounds aren't nice, but also yahoos wanted to rip apart the tables or cut them for firewood. Idiots.  The Central coast is beautiful, cold water tho.

One thing I wanted to do is the train trip from either Seattle or Vancouver across the rockies, it is a big WOW! I took the train from LA to New Orleans and the western geology is what stands out, once we got to greaner eastern states it's not that visually fun.

The other train trip I took was LA to Santa Fe, WOW! That small city is beautiful and colorful, friendly and Taos is a bit away and higher up.

There was a news article recently and Yosemite was a parking lot but winter descends early so right after school starts or before it begins.  Plus they had a big fire near by and the smoke left everything hazy.  Even the Grand Canyon is so hazy summers, I had a trip there 35 years ago and hiked down and back up the next day.... NEVER again!  I was in shape, but don't do it if you aren't really fit.

I do want to go to the other great Western parks but it's getting so expensive to travel.

At Lees Ferry you can drive right down to the Colorado River which is the river that flows through the GC, so I can claim that I have driven into the GC.